Refrigerant Pipe Pressure Test; Adding Pressure Operation; Control Diagram For Adding Pressure By Stages - York R-410A Technical & Service Manual

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♦Do the vacuum drying procedure (see the YDS refrigerant pipes vacuum drying in detail)
7) Close the nitrogen main valve.
8) Repeat the above operations.
9) After finishing flushing the liquid pipes, then flushing the gas pipes.

4.6.6 Refrigerant pipe Pressure Test

1. Adding pressure operation

(1) During pressure test, the valves on gas side and liquid side should be full-closed.
Because nitrogen may enter into the outdoor circulation system, strengthening the valves before
adding pressure operation.
(2) For every refrigerant system, add pressure slowly and orderly from gas and liquid side.
(3) And the gas used must be nitrogen. Carbon Dioxide will probably condense. And Oxygen
will probably cause explosion.
(4) The time must be over 24h in the third-phase of adding pressure.
(5) Sketch map of adding pressure.

2. Control diagram for adding pressure by stages0.

No.
1 Add pressure 3.0kgf/cm
2 Add pressure 15.0kgf/cm
3 Add pressure 28.0kgf/cm
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Phase (add pressure by stages)
2
G for more than 3 minutes to check big leakage.
2
G for more than 3 minutes to check big leakage.
2
G for more than 24 hours to check small leakage.
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Installation
Standard
No pressure
falling